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#
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#   documentation and/or other materials provided with the distribution.
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import bifrost as bf

import threading

from bifrost import telemetry
telemetry.track_module()

class TempStorage(object):
    def __init__(self, space: str):
        self.space = space
        self.size  = 0
        self.ptr   = None
        self.lock  = threading.Lock()
    def __del__(self):
        self._free()
    def allocate(self, size: int) -> "TempStorageAllocation":
        return TempStorageAllocation(self, size)
    def _allocate(self, size):
        if size > self.size:
            self._free()
            self.ptr = bf.memory.raw_malloc(size, self.space)
            self.size = size
    def _free(self):
        if self.ptr:
            bf.memory.raw_free(self.ptr, self.space)
            self.ptr  = None
            self.size = 0

class TempStorageAllocation(object):
    def __init__(self, parent: TempStorage, size: int):
        self.parent = parent
        self.parent.lock.acquire()
        self.parent._allocate(size)
        self.size = parent.size
        self.ptr  = parent.ptr
    def release(self) -> None:
        self.parent.lock.release()
    def __enter__(self):
        return self
    def __exit__(self, type, value, tb):
        self.release()
